End cover assembly, housing assembly, battery cell, battery, and electric equipment

Abstract

An end cover assembly includes: an end cover with a through hole for injecting electrolyte and a first clamping portion, wherein the first clamping portion is disposed along a circumferential direction of the through hole and is located on one side of the end cover away from an interior of the battery cell; a sealing ring for sealing the through hole; and a pressure relief device covering at least part of the sealing ring and closing the through hole; wherein the pressure relief device includes a second clamping portion, and is rotatable such that when the pressure relief device is rotated to a first position, the second clamping portion is clamped with the first clamping portion; and when the pressure relief device is rotated to a second position, the second clamping portion is disengaged from the first clamping portion.

The invention claimed is: 
     
       1. An end cover assembly for a battery cell, comprising:
 an end cover provided with a through hole for electrolyte injection and a first clamping portion, wherein the first clamping portion is disposed along a circumferential direction of the through hole and located on one side of the end cover away from an interior of the battery cell; 
 a sealing ring for sealing the through hole; and 
 a pressure relief device covering at least part of the sealing ring and closing the through hole, wherein the pressure relief device is configured to be destroyed when an internal pressure of the battery cell reaches a threshold, so as to remove a closure of the through hole and release the internal pressure of the battery cell; 
 wherein the pressure relief device comprises a second clamping portion and is rotatable such that when the pressure relief device is rotated to a first position, the second clamping portion is clamped with the first clamping portion to limit separation of the pressure relief device from the end cover, and when the pressure relief device is rotated to a second position, the second clamping portion is disengaged from the first clamping portion to realize separation of the pressure relief device and the end cover, 
 wherein the first clamping portion is one of a clamping slot and a clamping column, and the second clamping portion is the other of the clamping slot and the clamping column, and 
 wherein in a height direction, the first clamping portion is not lower than a position of the sealing ring. 
 
     
     
       2. The end cover assembly according to  claim 1 , wherein the pressure relief device comprises a main body portion and a pressure relief member, the main body portion is connected to the second clamping portion, the pressure relief member closes the through hole, and the pressure relief member is configured to be destroyed when the internal pressure of the battery cell reaches the threshold to release the internal pressure. 
     
     
       3. The end cover assembly according to  claim 2 , wherein the pressure relief member and the main body portion are integrally or separately disposed. 
     
     
       4. The end cover assembly according to  claim 3 , wherein
 the pressure relief member and the main body portion are disposed separately, and the pressure relief member is disposed between the main body portion and the sealing ring; and/or 
 the pressure relief member comprises a metal layer and a protective layer, the protective layer and the metal layer are disposed in a laminating manner, and an elongation rate of the protective layer is greater than an elongation rate of the metal layer. 
 
     
     
       5. The end cover assembly according to  claim 4 , wherein the pressure relief device further comprises a separation ring, the separation ring is disposed between the main body portion and the pressure relief member so as to separate the main body portion from the pressure relief member to protect the pressure relief member. 
     
     
       6. The end cover assembly according to  claim 5 , wherein the separation ring is attached to the pressure relief member. 
     
     
       7. The end cover assembly according to  claim 3 , wherein the pressure relief member is an aluminum plastic film. 
     
     
       8. The end cover assembly according to  claim 2 , wherein the pressure relief device comprises at least two pressure relief members connected to each other, such that when the internal pressure of the battery cell reaches the threshold, an interconnected part of the at least two pressure relief members is broken through to release the internal pressure. 
     
     
       9. The end cover assembly according to  claim 8 , wherein
 the at least two pressure relief members are butted or partially overlap; and/or 
 the at least two pressure relief members are connected by means of heat sealing. 
 
     
     
       10. The end cover assembly according to  claim 9 , wherein the at least two pressure relief members partially overlap, and an overlapping part of the at least two pressure relief members protrudes to one side away from the sealing ring relative to remaining parts of the at least two pressure relief members. 
     
     
       11. The end cover assembly according to  claim 10 , wherein
 the overlapping part of the at least two pressure relief members is bent to reduce a height of the overlapping part; and/or 
 a separation ring of the pressure relief device is provided with an accommodating slot, and the overlapping part of the at least two pressure relief members is accommodated in the accommodating slot. 
 
     
     
       12. The end cover assembly according to  claim 1 , wherein
 the pressure relief device is provided with a groove, and the sealing ring is located in the groove. 
 
     
     
       13. The end cover assembly according to  claim 1 , wherein the end cover assembly further comprises a guide slot, the guide slot is in communication with the clamping slot, such that during rotation of the pressure relief device, the clamping column enters and exits the clamping slot through the guide slot. 
     
     
       14. A battery cell, comprising:
 an electrode assembly and a shell for accommodating the electrode assembly, wherein the shell comprises a housing and the end cover assembly according to  claim 1 , the housing has an end opening, and the end cover assembly covers the end opening of the housing. 
 
     
     
       15. A battery, comprising at least two battery cells according to  claim 14 . 
     
     
       16. An electric equipment, comprising the battery cell according to  claim 14 , wherein the battery cell is configured to provide electric energy.